Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 438

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-438 A Harbor Springs MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348      
231-438 2 Harbor Springs MI GDRPMIBL04Z  543C ONVOY, LLCV - MI 348   2023-09-16   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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